It was easy to see how the Snivy would mistake you for "the bad guys", you think at first, but perhaps that wasn't quite it. Were that the case, it would've fought back with much more vigor than it had - you vividly recall it simply dodging Monte's attacks, rather than riposting. On second thought, it seemed the Snivy was more interested in keeping you quiet - hence why it restrained Éclair and even encouraged you to recall your tiny warriors.

It would make sense; the Snivy seemed to have been caught in the web of the criminal who'd made all those hostages. At first, it could be assumed it worked at the factory itself, but the badge said "Port Guard". It is then that you recall what Captain Trent Gatt had told you: "the guard stationed here at Bullarum caught them breaking in. They made the man hostage, along with the workers of that canned Finneon factory."

This could well be the Snivy belonging to that brave lone guard that had first crossed paths with the Pokémon trafficker, the very first hostage. It would make sense that the Grass-Type would want to save its master, as well as the other twenty hostages, likely having been raised to handle just this kind of high-stress situations. It would explain its higher level, too, and why you weren't able to land a hit.

Snivy looks at you, relieved you seem to be on its side after all, then dutifully proceeds to request your assistance. Like a miniature spec-ops soldier, it goes on to explain the layout of the situation like a pro would (if only it didn't look so adorably squishy at the same time, it could pass off as a serious badass, you think). It summons a whirl of leaves, as silently as it can, and lets them drop on the metal walkway floor, covering it. Then, using its vines, it begins to push some of the leaves away, effectively drawing a makeshift map of the factory!

You can see the stairs leading down to the ground floor, as well as a number of rooms. At the far end of the floor, near the front door, is an amalgam of leaves that likely represent the hostages, as well as the criminal busy bringing the fight to Gatt's men on the outside. On some of the rooms, as well as the corridors, a lone red leaf likely represent "guards" left behind by the criminal in case someone attempts to sneak up on him - six in total, exactly the number of Pokémon a Trainer can carry at once.

If you understand Snivy's plan, the intention is to make way along the ground floor, from back to front, neutralizing these guards as you go along until you reach the criminal... but even Snivy’s knowledge of the plant is rudimentary, and there is no telling what each room is for, or what kind of enemy lurks inside.
It seems risky, especially since you don't know what you're up against. In case you decide to go all the way with this, you should prepare in advance... what will you do?

The more she interacted with the Grass Snake, the more Athena understood its intentions. Though she would have rather it kept its vines away from strangling Eclair, the determined look on its face told her that they were in a very serious situation. It was definitely skilled, definitely much more so than herself and her Pokemon.

She took a step back as the Pokemon called forth a whirlwind of leaves. As the leaves settled on the ground, it begin to work hard at crafting something. Athena watched silently, fighting the urge to take a video on her phone. Snivy let her look when it finished, presenting a what seemed to be a map of factory, along with red leaves marking potential opponents. Athena traced over the map with a finger, careful to not to move any of the leaves from their positions.

"I think...I get it?" She whispered to the Pokemon. During slow times at Laverre Cafe, she enjoyed working on the occasional puzzle game, and this seemed somewhat similar. Though she couldn't be sure what this path held, her Pokemon and this Snivy could probably take down each 'guard' on their way. She counted 6 guards, was it really necessary to take all of them out? At the same time, she didn't want to be ambushed from behind by anyone they neglected to go after. Though Snivy had a bit more information than she did, they were both mostly in the dark. It seemed best here to just go for it, and adapt to whatever was thrown at them.

Careful to not make too much noise with the zipper, Athena retrieved a Pokeball from her backpack. She pressed the center button, and held it out to reveal a quadrupedal Pokemon in a flash of light. The Stufful materialized on the ground, and Athena knelt down next to her.

"Mille should be quiet with these feet," Athena told Snivy, picking up one of Mille's legs to show him how plush she was. Mille yanked her limb back and huffed, not in the mood to be shown off by her trainer. "I can be quiet too." She removed her shoes, leaving her only in socks decorated with pictures of cat Pokemon like Litten and Meowth. She stood, and motioned to Snivy that she was ready to go and take on the first guard.